export html page to pdf on user click using javascript.

JavaScript
$(function () {

    var specialElementHandlers = {
        '#editor': function (element,renderer) {
            return true;
        }
    };
 $('#cmd').click(function () {
        var doc = new jsPDF();
        doc.fromHTML(
            $('#target').html(), 15, 15, 
            { 'width': 170, 'elementHandlers': specialElementHandlers }, 
            function(){ doc.save('sample-file.pdf'); }
        );

    });  
});$(function() {
  var doc = new jsPDF();
  var specialElementHandlers = {
    '#editor': function(element, renderer) {
      return true;
    }
  };
  $('#cmd').click(function() {
    doc.fromHTML($('#target').html(), 15, 15, {
      'width': 170,
      'elementHandlers': specialElementHandlers
    });
    doc.save('sample-file.pdf');
  });
});
Source

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